Ian Poulter confirmed his reputation as one of golf's most indefatigable competitors on Sunday as he capped a succession of comeback wins at the Volvo World Match Play Championship in Spain with a yet another unlikely victory, over Luke Donald in the final.

Poulter, who had been down three times in the match, holed a 10-foot putt on the penultimate green at the Finca Cortesin club to defeat his Ryder Cup colleague 2&1 and take the £704,000 winner's cheque. The disappointment for Donald was compounded by the fact that the defeat meant he missed out on a chance to usurp Lee Westwood as the world No1. It is the second time in a month that Donald has come up just short when in with a chance of topping the world rankings. "It's disappointing. I ran out of steam at the end and you have to hole putts to win," he said.

Never a truer word was spoken in golf, and never have Poulter's strengths been so obvious as this week. He putts brilliantly under pressure and never gives in, as he showed on Saturday when he birdied the final three holes to overcome a two-hole deficit to Francesco Molinari in the quarter-finals. There was more of the same on Sunday morning against Nicolas Colsaerts of Belgium, who was three-up at one stage in their semi-final before the Englishman reeled him in by the 16th and sent him to defeat at the first extra hole.

"I just kind of hung in there and you just need a bit of momentum," Poulter said after that contest. "I think experience was crucial. Nicolas had the upper hand with length [he was the Tour's biggest hitter last season] and I just had to trust my short game."

It has ever been thus for Poulter, whose distance off the tee leaves him at an obvious disadvantage in an era in which long-hitters tend to dominate. Yet what Poulter lacks in length he makes up for with tenacity and a putting stroke that seldom falters in the crux, as has been the case in the last two Ryder Cup events.

His short game also carried him to victory at last year's Accenture World Matchplay in Tucson. He has won on the European tour since then – in Hong Kong at the end of last season – but he has had only one top-10 finish in 2011. "I've had spells like this before. I'm not worried," he said last week. "In golf things can turn around very quickly."

They can indeed, although perhaps not even Poulter himself might have imagined that his fortunes would have changed so dramatically in such a short space of time.

Over the past three months there can be little argument that Westwood and Donald have played the best golf in the world on a consistent basis – Poulter beat both men in Spain; the former in a wonderful contest in the round of 16 that went all the way to the 18th green.

The final on Sunday did not quite reach the same standard, but it was enthralling nevertheless. Donald took the lead at the 2nd with a par, then bogeyed the 4th and 5th to fall behind. His 25-footer at the 6th for a birdie two left the match level once more.

Back and forth it went after that, with Poulter's tumble after losing his balance on the 8th even leaving him without his lucky ball-marker, until it was retrieved by a referee. He levelled at the next and again with a 40-footer at the short 12th after bogeying the 226‑yard 10th, then went ahead for the second time thanks to a pitch to three feet on the 14th.

Donald had a chance to draw level again on the 15th but missed from three feet and had to settle for a half. That was not the decisive blow but its effect on the world No2's morale was plain to see, though perhaps it was not as obvious as Poulter's approach shot at the 16th, which finished two feet from the hole.

Two up with two to play, he needed to hole a 10-foot putt for par on the 17th to win and, unsurprisingly, he did exactly that.

Afterwards, Poulter dedicated his victory to his son Luke, who was celebrating his seventh birthday back home in Florida. "It's a nice boost. Plenty of questions have been asked of me over the last five months," he said.